van amstel



Sept. 4, 1923. I

' A. F. VAN AMSTEL INTERNAL COMBUSTION ENGINE Filed Nov.-1l 1920 2Sheets-Sheet 1 PL/ww mm 5 N N 5% W H m E5 N A m w 8 w w m Sept.' 4,1923;

A. F. VAN AMSTEL INTERNAL COMBUSTION ENGINE Filed Nov. 11, 1920 PatentedSept. 4, 1923.

UNITED STATES ADRIAAN FREDERIK VAN AMSTEL, OF AJEERS EOORT, NETHERLANDS.

INTERNAL-COMBUSTION ENGINE.

Application filed November 11 1920. Serial No. 423,439.

To all whom it may concern:

Be it known that I, ADRIAAN Fnnnnnrx VAN AMsTEL, a subject of the Queenof the Netherlands, residing at Amersfoort, in the Province of Utrecht,in the Kingdom of the Netherlands, have invented certain new and usefulImprovements in Internal-Combustion Engines; and I do hereby declarethat the following is a full, clear, and exact de- 1 scription of thesame.

My invention relates to internal-combustion engines of the type whereinthe cylinder is in constantly open communication withan auxiliarychamber through a perma- 15 nently restricted passage and wherein theliquid-fuel nozzle opens into the motor in such. a way, that the fueljet issues from the nozzle in a direction through the restricted passageto the cylinder.

In internal-combustion engines of the type referred to, the fuelinjection starts before the end of the compression stroke of the motorwhen, due to the compression, the self-ignition temperature of the fuelhas been reached. Through the connecting passage between the cylinderand the auxiliary chamber air then flows from the cylinder into theauxiliary chamber and the first injected particles of fuel, whileleaving the fuel inlet opening, are drawn by the stream of air into theauxiliary chamber. This is brought about in order that said particles offuel be ignited in said auxiliary chamber, so that the pressure in saidchamber increases, whereby the flow in the connecting passage isreversed and the remaining fuel is blown into the cylinder in the formof spray. This mode of operation however involves the followingdrawbacks. The auxiliary chamber is not large and usually has only avolume of about one twentieth of the volume of the compression space ofthe motor and therefore,-even in rather large engines, can only containa quantity of air sufficient to-completely burn some milligrams of fuel.So it may happen that more fuel flows into the. auxiliary chamber, inconsequence whereof incomplete combustion will take place therein sothat the chamber grows foul. Furthermore the efflux of gases from theauxiliary chamber into the cylinder is not always sufficientto'pulverizethe fuel driven into the cylinder, e. g., when the motor runs slowly anda maximum of fuel is supplied, the pressure in the auxiliary chamberdecreases too rapidly with respect to the speed of rotation of the motorto obtain a sufliciently fine spraying during the last part of the fuelinjection.

My invention consists in that a spreader is,

disposed before or in (or partly before and partly in) the cylinder endof the restricted passage between the cylinder and the auxiliary chamberso that the fuel jet which is injected through this passage, into thecylinder, on meeting the spreader, is broken up into spray, orvaporized, or partly pulverized and partly evaporated.

V The fuel ispreferably injected in a solid or almost solid, rodlike andthin jet against the spreader and by giving said fuel a high pressure itis pulverized into extremely small particles which guided by thedeflecting sur face or deflecting surfaces of the spreader diverge infavorable directions. The shape, the dimensions and the location of thespreader may be chosen in such a manner, that the injected fuel istotally or partly vaporized or even ignited by the heat of the spreader.The fine subdivision of the fuel therefore does not depend on unreliablefuel spraying by a current of gases and in combination with the workingof the auxiliary chamber a device is obtained, which can be applied tohighcompression and low-compression engines, as well as to motors withconstant pressure and such engines in which the pressure increases ordecreases during the combustion.

The advantages obtained by the invention can .be explained more clearlyby describing a few examples. The invention therefore will now be morefully explained with reference to the annexed drawings, in which a fewembodiments of the invention in the form of motor parts are shown,somewhat diagrammatically and not drawn to scale, for as much as isnecessary for a thorough understanding of the invention. a

Fig. 1 shows, partly in section, a part of a high-compression engine,provided With an arrangement according to the invention.

Figs 2 and 3 show, also partly in section, parts of engines in which anauxiliary chamber provided with an arrangement according to theinvention, extends beyond the cylinder head of the engine.

nec'ungp s'a e to spread sideways.

"Figf'9' shows a section of an auxiliary chamber with a heat accumulatorin the top Referring to Fig. 1, 1 indicates the engine cylinder,"2 thewater jacket, 8 the cylinder valve, 6 the auxiliary chamber and 7 thespreader. The engine is" started by rotating the crank shaft'by handorin any other well known manner. The motor is a twostroke or afour-stroke cycle engine. The airis'drawn or induced ina known mannerinto the cylinder 1 and iscompressed therein by'thepiston (not'shown) tosuch a volume, that its temperature rises beyond the self-ignitiontemperature of the fuel, before the fuel injectionstarts The latterstarts before the end of the compression strokefl'Thefuel inlet opensinto the auxiliary'chainbentj and the fuel is shot in a thin, solid jetfromjthe nozzle 8 through the connecting passage 9 upon the centre ofthe spreader 7. Thefuel spreads in the cylinder, in which it is rapidlyburnt. The burnt gases 'arfe driven in a well .known manner from thecylinder and the up and down movement of the piston is effected andutilized in the usual way. In this embodiment theauxili'ary"cliamber 6serves to promote the turbulence in the -cylinder and to blow clean thepassage 9, the spreader 7 and the edge ofthe nozzle 8 after the fuelinjection has been completedso that such parts cannot become foul oruncleanby a crust being formed. Vhether at the moment in whicl'rthe fuelinjection is completed a current of gases flows from the cylinder 1through the connecting passage 9 to the auxiliary chamber 6, or whetherthis movement takes place in opposite direction, depends oncertaincircumstances, butno matter in what direetio'n the gases may travel, theobject'in view is attained. If gases pass from the cylinder into theauxiliarychamber 6, so that a small quantity of fuel, which, e. g., hasstuck tetheedge' of the nozzle 8, is driven into the auxiliary chamber,then this fuel immediatelytakes fire due to the heat of the stream ofgases, in consequence whereof the movement in the passage 9 is reversedby the increase of pressure arising in said auxiliary chamber, or suchreversal takes place du'e'to the decrease ofpressure in the cylindercaused by the expansion of its contents during the working stroke. Thenozzle 8 is preferably so shaped, that the fuel jet is shot through thepassage 9 without touching the walls thereof and the injectionpreferably takes place in such a manner, that thefuel, before it passesalong the valve 5 into the nozzle 8, during the total injection, i. e.,also at the beginning as wellas at the end thereof, stands under ahigher pressure than the pressure prevailing in the cylinder 1. Thearrow shown in the drawing indicates one of the radial directions whichthe particles of fuel after leaving the deflecting surface take aroundthe spreader through the combustion space, provided that such particlesare not driven from their course by the flow of gases. Such fuel, as isalready vaporized while leaving thespreader 7, easily passes into andmixes with the flowing gases in the cylinder, and inorder to cause partof the fuel to penetrate as far into the cylinder as possible, it isdesirable to make the spreader T as small as possible, so thatit'accumulates a minimum of heat from the combustions in the cylinder,and the convex deflecting or spreading surface shortly after thestarting of the fuel injection, is cooled by the first particles of fuelto such an extent, that the subsequent particles of fuel leave thespreader in a liquid state, i. e., in the form of extremely smallglobules, Whether the engine .works with constant combustion pressure orwith increasing combustion pressure depends on the fuel injection. Ifthe fuel be'injected in a short time, then the pressure in the cylinderincreases during the combustion, and if it be injected in such a manner,that the injection continues dur ing a certain part of the power strokeof the piston it may be arranged in such a way, that the combustiontakes place with a constant or decreasing pressure.

In the case of the engine according to Fig. 2 the cylinder 1, the waterjacket 2 and the head 3 are formed in one piece, whilst the auxiliarychamber is formed partly outside the head 3 and the spreader 7 partlyprojects into the connecting passage 9. In the case of this constructionthe dimensions of the spreader are such, that it takes up more heat bythe combustions, in order to promote the vaporization of the fuel. Theuppermost part of the spreader has the shape of a cone, the apex ofwhich is some what rounded and the fuel jet is directed against thecentre of the rounded apex. The compression of the motor does notsufiice to reach the ignition temperature of the fuel in the cylinder,but a temperature beyond the self-ignition temperature of the fuelprevails in the auxiliary chamber 6 or is brought about therein by thecompression since the auxiliary chamber and the three rings 10 locatedtherein are hot. Though in using diflicultly vaporizing fuel, thetemperature of the air in the cylinder, before combustion startstherein, remains below the boiling point of the heaviest parts of thefuel, the fuel still vaporizes totally or partly, before, after leavingthe spreader, it reaches the piston. The liquid vaporizes, even if thetemperature is below the boiling point as long as the air is notsaturated with vaporized fuel. As the fuel drops are very small and movewith a high speed, so that a large fuel surface each time comes intocontact with other particles of air, such fuel drops vaporize easily.After the beginning of the compression stroke a stream of air passesfrom the cylinder into the auxiliary chamber 6 through the gap betweenthe spreader 7 and the wall of the cylinder end of the passage 9. Alongwith this stream of air vaporized fuel passes into the auxiliarychamber, inwhich it takes fire. Such influx of fuel is promoted by thefact that a por tion of the fuel leaving the cone-mantleshaped spreadingsurface of the member 7 collides against the bracket of the spreader andconsequently is deflected in such a way, that it is guided into thestream of air to the auxiliary chamber. Near or at the beginning of thepower stroke of the piston, the pressure in the auxiliary chamber beginsto surpass the pressure in the cylinder, so that burning gases from theauxiliary chamber pass into the cylinder and ignite the contentsthereof, whilst at the same time the mixture of the contents of thecylinder is strongly promoted. In the case of this embodiment thecombustion in the cylinder or main combustion space only starts when allthe fuel or part thereof has already mixed with the air in the cylinder.If the selfignition temperature of the fuel permanently prevails in theauxiliary chamber 6, i. e., also at the beginning of the compressionstroke, such fuel maybe injected early. In using very volatile fuel suchas petrol the inject-ion may even start before the beginning of thecompression stroke. Since fuel entering the auxiliary chamberimmediately takes fire therein, no sudden increase of pressure iseffected, but rather a gradual one and the pressure in the auxiliarychamber only begins to surpass the pressure in the cylinder when thecompression and therefore the increase of pressure in the cylinder drawsnear the end. The combustion therefore spreads from the auxiliarychamber into the cylinder not long before the end of the compressionstroke. If however the ignition temperature in the auxiliary chamber isnot reached but by the compression, then the fuel injection must startlate, during the compression stroke, since otherwise combustible mixturemight get into the auxiliary chamber, such mixture exploding therein notbefore the ignition temperature is reached. By this explosion a suddenincrease of pressure would be effected and an immediate ignition of thecontents of the cylinder might take place. As it is not certain at whatpoint of the revolution of the engine the ignitnon temperature in theauxiliary chamber is reached by the compression, in the case mentioned,a premature ignition of the cylinder contents might take place if thefuel is injected too early.

At the termination of the fuel injection in the case of this embodiment,the spreader 7, the passage 9 and the edge of the nozzle 8 are alsoblown clean by the current of gases flowing through the passage 9. Acurrent from the auxiliary chamber effects at the opening of the nozzle8 a strong whirlstream, which rapidly leads all particles of fuel,sticking to the edge or emerging from the aperture, into the cylinder.

In starting the cold engine the auxiliary chamber 6 is heated by meansof a lamp, through the opening 11 in the cap 12 of the auxiliary chamber6 and an opening 13 provided in the opposite side of said cap (theopening 13 is not shown in Figure 9., but it is shown in Figure 3). Assoon as the chamber 6 is sufficiently hot the engine may be started inthe manner stated h'ereinbefore. The spreader 7 is then cold, but it mayalso be preheated by rotating the engine a few times, without fuel.being injected. Thereby, after the compression stroke, hot air from theauxiliary chamber 6 is blown against the spreader so that it becomeshot. It is however not necessary to heat the spreader beforehand, sinceeven if it is cold, sufficient fuel is driven into the auxiliary chamber6 to obtain the initial combustion therein. Notwithstanding the lowtemperature of the spreader and the walls of the main combustion spacethe fuel jet totally or partly vaporizes in the cylinder, even if heavyfuel is used, since the liquid also vaporizes below the boiling point,as long as the air which comes into contact with it is not saturatedwith fuel vapour and since the temperature of the air is increased bythe compression. If during the first revolutions of the engine or evenlater when it is hot, fuel in a liquid state reaches the piston, theproper \vorkin is not influenced thereby, because such fuel vaporizesshortly after the'beginning of the combustion in the cylinder and burnscompletely. As soon as the rings 10, due to the heating of the auxiliarychamber from without and the combustions'in said chamber have becomesufficiently hot, said auxiliary chamber no longer requires to be heatedfrom without. The arrow in Fig. 2 indicates one of the radial directionsfollowed by the fuel drops around the member 7 after theirleaving thedeflecting surface.

1 tion takes place under high pressure.

the injection takes place with sufficient It is not necessary that thefuel inlet be closed by a valve Said inlet in that case may also leadfrom above through the cylinder head or it may be applied laterally, ase. g., shown in 3. In this case it is however desirable to design thefuel pump or accumulator, or in general the supply-means, in such a waythat after the injection is completed, the fuel does not remain in thefore part of the outlet opening of the nozzle 8, but is somewhatwithdrawn in order to prevent the fuel, due to the de crease of pressurein the cylinder, from afterwards flowing from the nozzle 8 by reason ofcontraction of the walls of t inlet pipe and expansion of the fueltherein. The arrow in Fig. 3 also indicates the course taken by aparticle of fuel after it has left the spreading surface, inasmuch as itis not influenced by the flow of gases from or into the passage 9. Inthe or so of this construction the spreader 7 projects into the passage9 and is smaller than in the case of the embodiment shown in Fig. 2. The

dimensions of the spreader may be chosen more or less large inproportion to the fuel used. In using volatile fuel a smaller spreadermay do than in using more diffioultly vaporizing fuel, in. order toobtain that sufficient fuel be vaporized and be mixed in that state withthe air in the cylinder, before the combustion in the cylinder starts.In the case of the embodiment according to Fig. 3 only two rings 10 areprovided and the lower one of them is placed upon. a ring 14:, restingupon a ring 15, the latter being made of non-conducting material.

In the embodiment shown in l the spreader is so dis-posed and thecylinder end of the passage 9 is so narrow, that no fuel can flow intotheauxiliary chamber be fore the fuel injection is completed or nearlycompleted, provided that the injecforce, an ejector action may becreated so that air from the auxiliary chamber s drawn thereby into thecylinder notwithstanding that a higher pressure prevails in the cylinderthan in the auxiliary chamber. In the case of this arrangement thecombustion in the cylinder cannot start, before the fuel injection iscompleted and under certain circumstances this may be preferable,

if using a small. auxiliary chamber, in order to obtain by making thepassage 9 narrower a thin flame of sufficient length shooting into thecylinder after the ignition in the auxiliary chamber. The spreadingsurfaces of the member 7 have the shape of a circle and a cone mantle.

In Fig. 5 an arrangement is shown in which the fuel jet also passesthrough a narrow portion of the passage 9, whereby fuel is drawninto theauxiliary chambe and the ignition takes place not before the fuelinjection has been completed. In the case of this embodiment thespreader is substantially larger so that also heavy fuel is rapidlytotally or partly vaporized by the heat of the spreader, as soon as thelatter, after a few combustions have taken place, is sufiicientlyheated. The dimensions of the spreader may also be such, that it becomessufiiciently hot to ignite the fuel, in which case the ignitionimmediately takes. place, or shortly after the commencement of theinjection. The fuel is first spread by the upper conical face of thespreader and then the drops pass immediately along the lower conicalface thereof. The said two conical faces may also be united intoa singleone, according to Fig. 6, so that the fuel comes into contact with thislarge surface, which may be useful when using very diflicultlyvaporizing fuel.

It is obvious, that the above described examples only show a few of theembodiments of the invention, which might be in creased by a largenumber. The engines according to Figs. 2, 3, 4L and 5, e. g., mightserve as high-compression motors, if the compression space he madesufficiently small and then it is not necessary to heat the auxiliarychamber beforehand, since the ignition temperature, even when the engineis cold, is reached in the air of combustion by the compression. In theembodiments shown in Figs. 2 and 5, in this case, the spreader need notbe large and in all the engines to which the said four figures relatethe fuel injection is preferably started near the end of the compressionstroke when the self-ignition temperature in the air in the cylinder hasbeen attained.

The shape imparted to the spreader is such that the fuel is spreadthereby in the most advantageous directions. If the shape of thecombustion space is disclike and the location of the spreader issuitably chosen, it may also be flat. In Fig. 7 a cylindrical spreaderis shown, partly in section, said spreader being secured to the piston,so that no fastening means in the Way of the fuel are necessary and thedeflecting surface is concave, so that a fuel jet, being directed uponit in the direction of the axis, is spread upward. In Fig. 8 a spreaderis shown in elevation, by which the fuel jet directed thereupon throughthe passage 9 is not spread around and which may he used if the passage9 is not in the centre of the cylinder head, but at the side thereof.

It is not necessary that the hot rings 10 always lie on the bottom ofthe auxiliary chamber. Under certain circumstances they.

may also be placed higher or even in the top. According as the rings liehigher in the auxiliary chamber, a h gher increase of pressure iseffected therein by the combustion in the auxiliary chamber, becausethen more combustible mixture flows into said auxiliary chamber beforethis takes lire in the heat zone (at the rings 10), unless in the spaceof the chamber under the rings the self-ignition temperature of the fuelalready prevails, in which case the arrangement of the rings makes no orlittle difference. In Fig. 9 an auxiliary chamber is shown in section,in the upper part of Which a hot ring 10 is arranged. By omitting thering 16 or placing it above the ring 10 the latter is about in themiddle of the chamber 6.

It is understood that the invention may be applied to one-cylinder aswell as to multi-cylinder engines and also to hori zontal as well as tovertical machines, Whilst per cylinder more than one auxiliary chamberprovided with the arrangement according to the invention may bearranged.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatWhat I claim is In an internal-combustion. engine, the combination of acombustion chamber, an auxiliary chamber in constantly opencommunication with said combustion chamber through a permanentlyrestricted passage, a spreading-member, and a nozzle adapted to injectfuel into said combustion chamber in such a way that said fuel beforeentering said combustion chamber moves through said restricted passage,and on that Wise that said fuel after issuing from said nozzle hitsagainst said spreading-member, and substantially coheres together untilit has struck said spreadingmember.

In testimony whereof I have aiiixed my signature in the presence of twoWitnesses.

ADRIAAN FREDERIK van AMSTEL.

Witnesses:

ANTON DER NAYTEGARD, AN'roNIo ELBnR'ro DOYER.

